1. Field of the Invention
The present invention relates to the field of handling, feeding and dispensing particulate materials.
2. Description of the Background Art
A variety of devices have been proposed for handling and dispensing dry particulate materials, such as flour, sugar and grain. For example, U.S. Pat. No. 2,905,365 discloses a dispenser with a hopper having a vibrating screen therein. U.S. Pat. No. 2,633,242 discloses a flour duster including an outer housing open at the bottom with a perforated screen plate forming the bottom wall of the hopper. U.S. Pat. No. 2,390,195 discloses a flour duster including a curved bottom screen with an agitator bar and rotating brush therein. U.S. Pat. No. 2,323,864 discloses a vibratory feeder including a vibrating hopper and vibrating tray. U.S. Pat. No. 2,066,899 discloses a flour dusting mechanism including a hopper having a perforate bottom and an agitator mechanism. U.S. Pat. No. 1,926,903 discloses a sifter mechanism having a stationary hopper with rocking agitators comprised of longitudinal rods therein. U.S. Pat. No. 1,537,123 discloses a dry feeding machine having a vibrating hopper section with rotating agitator means therein. U.S. Pat. No. 1,181,208 discloses a candy starching device with a vibrating screen sifter and a rotating assembly within the hopper. U.S. Pat. No. 311,904 discloses a grain separator and cleaner with a vibrating screen assembly. U.S. Pat. No. 52,693 discloses a drug and spice sifter including a curved screen and rotating assembly therein, and U.S. Pat. No. 44,785 discloses a plaster and seed sower including a dual-chamber hopper with rotating devices in each chamber.
The above-described devices were intended for use with dry, non-sticky granular and powdered materials such as flour, sugar and grains. Certain seasoning materials which would be desirable to use as topical seasonings sprinkled on snack foods are extremely difficult to handle, feed an apply on an industrial or commercial scale. For example, granular particles formed of seasoning materials having up to 50% fat or more can become very sticky and tend to agglomerate and clog up previously known devices for feeding dry particulate materials such as flour, sugar and grains. Because of this, prior art devices for dispensing non-sticky granular and powdered materials are generally unsuitable for uniformly dispensing high fat content particles that are sticky, and which agglomerate and smear when compacted or worked. As a consequence, snack food manufacturers previously have either had to forego the use of such agglomerable high fat seasoning materials, or put up with non-uniform seasoning of snack food products using prior art dispensers.
Accordingly, there remains a need in the art for a method and apparatus for uniformly dispensing seasoning materials that tend to agglomerate and smear when compacted or worked.